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<main id="resize">
<h1 class="title">resize</h1>
<p class="subtitle" id="resize-an-image">Resize an image</p>
<div class="contents topic" id="contents">
<p class="topic-title">Contents</p>
<ul class="simple">
<li><p><a class="reference internal" href="#magnifyimage" id="id11">MagnifyImage</a></p></li>
<li><p><a class="reference internal" href="#minifyimage" id="id12">MinifyImage</a></p></li>
<li><p><a class="reference internal" href="#resizeimage" id="id13">ResizeImage</a></p></li>
<li><p><a class="reference internal" href="#sampleimage" id="id14">SampleImage</a></p></li>
<li><p><a class="reference internal" href="#scaleimage" id="id15">ScaleImage</a></p></li>
<li><p><a class="reference internal" href="#thumbnailimage" id="id16">ThumbnailImage</a></p></li>
</ul>
</div>
<section id="magnifyimage">
<h1><a class="toc-backref" href="#id11">MagnifyImage</a></h1>
<section id="synopsis">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *MagnifyImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="description">
<h2>Description</h2>
<p>MagnifyImage() is a convenience method that scales an image proportionally
to twice its size.</p>
<p>The format of the MagnifyImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *MagnifyImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<p>A description of each parameter follows:</p>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="minifyimage">
<h1><a class="toc-backref" href="#id12">MinifyImage</a></h1>
<section id="id1">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *MinifyImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id2">
<h2>Description</h2>
<p>MinifyImage() is a convenience method that scales an image proportionally
to half its size.</p>
<p>The format of the MinifyImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *MinifyImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<p>A description of each parameter follows:</p>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="resizeimage">
<h1><a class="toc-backref" href="#id13">ResizeImage</a></h1>
<section id="id3">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ResizeImage( <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns, const unsigned long rows,
                    const <a class="reference external" href="../api/types.html#filtertype">FilterTypes</a> filter, const double blur,
                    <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id4">
<h2>Description</h2>
<p>ResizeImage() scales an image to the desired dimensions with one of these
filters:</p>
<p>Bessel   Blackman   Box
Catrom   Cubic      Gaussian
Hanning  Hermite    Lanczos
Mitchell Point      Quandratic
Sinc     Triangle</p>
<p>Most of the filters are FIR (finite impulse response), however, Bessel,
Gaussian, and Sinc are IIR (infinite impulse response).  Bessel and Sinc
are windowed (brought down to zero) with the Blackman filter.</p>
<p>ResizeImage() was inspired by Paul Heckbert's zoom program.</p>
<p>The format of the ResizeImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ResizeImage( <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns, const unsigned long rows,
                    const <a class="reference external" href="../api/types.html#filtertype">FilterTypes</a> filter, const double blur,
                    <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>columns:</dt>
<dd><p>The number of columns in the scaled image.</p>
</dd>
<dt>rows:</dt>
<dd><p>The number of rows in the scaled image.</p>
</dd>
<dt>filter:</dt>
<dd><p>Image filter to use.</p>
</dd>
<dt>blur:</dt>
<dd><p>The blur factor where &gt; 1 is blurry, &lt; 1 is sharp.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="sampleimage">
<h1><a class="toc-backref" href="#id14">SampleImage</a></h1>
<section id="id5">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *SampleImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                    const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id6">
<h2>Description</h2>
<p>SampleImage() scales an image to the desired dimensions with pixel
sampling.  Unlike other scaling methods, this method does not introduce
any additional color into the scaled image. SampleImage() is extremely
fast and may be used where speed is most important.</p>
<p>The format of the SampleImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *SampleImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                    const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>columns:</dt>
<dd><p>The number of columns in the sampled image.</p>
</dd>
<dt>rows:</dt>
<dd><p>The number of rows in the sampled image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="scaleimage">
<h1><a class="toc-backref" href="#id15">ScaleImage</a></h1>
<section id="id7">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ScaleImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                   const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id8">
<h2>Description</h2>
<p>ScaleImage() changes the size of an image to the specified dimensions.
This method is reasonably fast but it is not currently multi-threaded
and does not support image filters. The quality of the resized image
is sufficient for most purposes.</p>
<p>The format of the ScaleImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ScaleImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                   const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>columns:</dt>
<dd><p>The number of columns in the scaled image.</p>
</dd>
<dt>rows:</dt>
<dd><p>The number of rows in the scaled image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
<section id="thumbnailimage">
<h1><a class="toc-backref" href="#id16">ThumbnailImage</a></h1>
<section id="id9">
<h2>Synopsis</h2>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ThumbnailImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                       const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
</section>
<section id="id10">
<h2>Description</h2>
<p>ThumbnailImage() changes the size of an image to the given dimensions.
This method was designed as a low cost thumbnail generator.
ThumbnailImage() is typically very fast but an attempt is made to improve
quality by first using a simple sampling algorithm for part of the
reduction, and then a filtering algorithm to produce the final image.</p>
<p>The format of the ThumbnailImage method is:</p>
<pre class="literal-block"><a class="reference external" href="../api/types.html#image">Image</a> *ThumbnailImage( const <a class="reference external" href="../api/types.html#image">Image</a> *image, const unsigned long columns,
                       const unsigned long rows, <a class="reference external" href="../api/types.html#exceptioninfo">ExceptionInfo</a> *exception );</pre>
<dl class="simple">
<dt>image:</dt>
<dd><p>The image.</p>
</dd>
<dt>columns:</dt>
<dd><p>The number of columns in the scaled image.</p>
</dd>
<dt>rows:</dt>
<dd><p>The number of rows in the scaled image.</p>
</dd>
<dt>exception:</dt>
<dd><p>Return any errors or warnings in this structure.</p>
</dd>
</dl>
</section>
</section>
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